For the record, the resolution was that I had two accounts, one an admin and one a superadmin (both with a similar username). I believe that my logging into an app as the admin caused my current account in Cloudron to also become admin. This hid the "Configure" button in the Backup section--while admins can see the backup settings, only the superadmin can change them. Logging out of the admin account immediately gave me access to superadmin again.
C
canadaduane
@canadaduane